Molar mass note
October 17, 2014
Recall Avogadro's Constant:
Yesterday, we practiced determining number of atoms/molecules/formula units in a certain number of moles.
Today, we will practice converting from moles to mass of a particular substance.
Oct 15­9:30 AM
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Molar mass note
October 17, 2014
Finding Molar Mass of Compounds
Example 1. Find the molar mass of NaCl.
Step 1. Identify the atoms that make up the compound.
Step 2. Identify how many of each atom there are in the compound.
Oct 15­9:26 AM
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Molar mass note
October 17, 2014
Step 3. Identify the molar mass of each atom ­ THIS IS GIVEN IN THE PERIODIC TABLE. Step 4. Add them all up!!
Oct 15­9:28 AM
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Molar mass note
October 17, 2014
Example 2. Find the molar mass of CaCl2.
Step 1:
Step 2:
Step 3:
Step 4:
Oct 15­9:33 AM
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Molar mass note
October 17, 2014
Example 3. Find the molar mass of CH3COOH.
Step 1:
Step 2:
Step 3:
Step 4:
Oct 15­9:34 AM
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Molar mass note
October 17, 2014
9. What is the mass of 3 moles of NO3?
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Molar mass note
October 17, 2014
Oct 15­12:15 PM
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